Field of the Invention
The present invention relates to a piezoelectric body including a piezoelectric element and a substrate for power feeding.
Description of the Related Art
Conventionally ultrasonic motors have been used for a lens barrel of an imaging apparatus or the like due to their features of being compact and light-weighted and driving speedily and silently. Such an ultrasonic motor typically includes a piezoelectric body as its source of vibration, and Japanese Patent Application Laid-Open No. 2012-16107 and Japanese Patent Application Laid-Open No. 2015-6047 disclose such an example. Hereinafter a piezoelectric element, to which a flexible printed circuit substrate (abbreviated as FPC) as power-feeding means is bonded, is called a piezoelectric body, a piezoelectric body, to which an elastic body is bonded, is called a vibrator, and a motor including a vibrator as its driving source is called a vibration wave motor.
In order to ensure the reliability of an electronic apparatus including a piezoelectric body, a vibrator, and a vibration wave motor (hereinafter they are abbreviated as “a piezoelectric body or the like”), the bonding part between the piezoelectric element and the FPC has to have sufficient mechanical reliability and electrical reliability. Herein, the mechanical reliability refers to strength and durability against breaks and peeling, whereas the electrical reliability refers to certainty in electrical connection and stability of electrical resistance. In order to allow an electronic apparatus including a piezoelectric body or the like to operate in harsh conditions and severe environment as compared with a current state, both of the mechanical reliability and electrical reliability have to be improved.